1. Field of the Invention
The invention of this disclosure relates to an apparatus with automatic belt tensioning and, more particularly, to an apparatus with automatic belt tensioning used in a head mount apparatus.
2. Description of the Prior Arts
Conventionally, a belt has to be used for helping mounting a head mount apparatus such as swimming goggles or a head lamp onto a head of a user. The length of the belt can be usually adjusted to be applied to heads of different users. Further, the belt usually has elasticity, and after the belt is stretched to be worn on the head, the contracting force of the belt makes the head mount apparatus firmly mounted onto the head. However, when different users wear the same apparatus, they have to adjust the belt to make the apparatus applied to their own head. Otherwise, the head mount apparatus is easily loosened, or the head of the user may bear too much stress.
In addition, another belt with automatic tensioning has a tensioning mechanism for automatically tensioning the belt after worn. Accordingly, the belt without elasticity can be used, thus greatly increasing selectivity of the material of the belt. In this kind of the belt with automatic tensioning, an elastic element in the tensioning mechanism is usually used to help winding the belt around a roller. When the belt is pulled by the user, the belt is stretched from the roller thus to be capable of being worn on the head of the user. After the belt is released, the belt may be wound around the roller by the elastic element again.
However, in this kind of the belt with automatic tensioning, the tensioning force of the elastic element is proportional to the stretching length of the belt, and therefore the user with a larger head may bear more stress. Further, based on the same principle, the tensioning force of the elastic element reaches the maximum at the moment that the belt is to be released after it is pulled by the user, and therefore the belt may be quickly wound around the roller again. At this moment, the belt may strike the head of the user, thus making the user feel discomfort.
Accordingly, the invention of this disclosure is to provide a better solution to improve the prior art.